ADLINK PCI-9524 - Manual (Page 85)

Operation Theory 69
ADLINK Technology Inc. PCI-9524
Copyright 2008 User’s Manual
4.5 Isolated Pulse-Command Generator
There are three opto-isolated differential pulse output channels in
PCI-9524, supporting typical servo amplifiers equipped with opto-
isolated inputs and/or differential line-receivers. Each pulse-com-
mand channel can be programmed to support single phase or dual
phase operations, including DIR/CLK and CW/CCW direction con-
trol.
The pulse-command generator has two operating modes, Burst
mode and Infinite Mode. The former generates user specified
pulses, while the later generates pulses continuously until a stop
command is issued by user's application.
The pulse frequency, and duty-cycle can be programmed through
a windows API, although most servo amplifiers accept a 50% duty
cycle as default.
Servo amplifiers using opto-coupler input stages generally accept
as high as 500-kHz pulses per second. For higher speed pulse-
command applications, use servo amplifiers with differential line-
receivers. Use twisted pair wiring for high-speed differential signal
transmissions to ensure low EMI leakage.
The pulse-command generator has a built-in pulse comparator
that generates an AD trigger signal when the number of pulses
generated has reached a user specified threshold.
4.6 Isolated Digital I/O
PCI-9524 supports eight channels of opto-coupler isolated digital
inputs, and eight channels of N-MOS sink drivers. Users can use
these I/O functions to control relays, actuators, bulbs, etc...